EXHAUST EMISSION CONTROL APPARATUS FOR INTERNAL COMBUSTION ENGINE

摘要

A NOx occlusion reduction type catalyst positioned in an exhaust path of an internal combustion engine, which can be used with the internal combustion engine to permit efficient use of ozone when ozone is added to an exhaust gas. A NOx oxidation gas supply device supplies air or ozone (O3) So that air or ozone (O3) mixes with an exhaust gas flowing into the NOx occlusion reduction type catalyst. The ozone supply is performed when the temperature of the NOx occlusion reduction type catalyst is lower than a temperature at which a NOx occlusion acceleration effect is produced by the air supply. After the temperature of the NOx occlusion reduction type catalyst reaches the temperature at which the NOx occlusion acceleration effect is produced by the air supply, the air supply is performed and the ozone supply is shut off.